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How do you append to a file in Python?
...ight think to forget it when the code has multiple exit points, exceptions and so on.
– Petter
Jun 13 '13 at 17:37
59
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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
...
Update
data.table v1.9.6+ now supports OP's original attempt and the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
...
Multi-key dictionary in c#? [duplicate]
...<T1,T2>(item1, item2);
}
}
You get immutability, .GetHashcode and .Equals for free, which (while you're waiting for C# 4.0) is nice 'n simple...
One warning however: the default GetHashcode implementation (sometimes) only considers the first field so make sure to make the first field t...
Create UIActionSheet 'otherButtons' by passing in array, not varlist
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I got this to work (you just need to, be ok with a regular button, and just add it after :
NSArray *array = @[@"1st Button",@"2nd Button",@"3rd Button",@"4th Button"];
UIActionSheet *actionSheet = [[UIActionSheet alloc] initWithTitle:@"Title Here"
...
UIPopovercontroller dealloc reached while popover is still visible
...anaged by the presentation controller.
Code example (works both on iPhone and iPad):
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
picker.allowsEditing = YES;
picker.modalPresentationSt...
How to open the Google Play Store directly from my Android application?
...CTION_VIEW, Uri.parse("market://details?id=" + appPackageName)));
} catch (android.content.ActivityNotFoundException anfe) {
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("https://play.google.com/store/apps/details?id=" + appPackageName)));
}
We use a try/catch block here because an E...
ruby system command check exit code
I have a bunch of system calls in ruby such as the following and I want to check their exit codes simultaneously so that my script exits out if that command fails.
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How to detect a textbox's content has changed
...box').on('input', function() {
// do your stuff
});
...which is nice and clean, but may be extended further to:
jQuery('#some_text_box').on('input propertychange paste', function() {
// do your stuff
});
share
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Any way to replace characters on Swift String?
...n history.
You have a couple of options. You can do as @jaumard suggested and use replacingOccurrences()
let aString = "This is my string"
let newString = aString.replacingOccurrences(of: " ", with: "+", options: .literal, range: nil)
And as noted by @cprcrack below, the options and range parame...
Change working directory in my current shell context when running Node script
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Oops. Ya, that is the command I am actually using. However, when I use it in a simple script it still does not seem to work (once the script exits I am still in the old directory) If I call process.cwd() it says I am in the directory I should be but ...